The Jacinth-Ambrosia mine in South Australia’s Eucla Basin is Iluka’s primary source of zircon. [2018 Annual Report, p. 38]

The Eucla Basin in southern Australia is one of the world’s largest onshore extents of Cenozoic marine sediments. Early Cenozoic coastal deposits remain largely intact and can be traced along a 2000 km basin margin that extends up to 380 km inland of the present day coastline. This includes over 650 km of coastal dune complexes along the northeastern basin margin that have been modified by aeolian processes to form the Ooldea and Barton sand ranges. Sand deposited along this coastline is the result of interaction between a dominant westerly wind, driving westerly longshore drift and building coastal dunes, and sea level change during Eocene to Miocene times.

Marine transgressions during the late Middle Eocene (39–36 Ma), Late Eocene (36–34 Ma), and Neogene (15–2 Ma) reworked beach and backshore dune deposits to concentrate HM in suitable trap sites (Hou et al. 2008; Hou and Keeling 2008). Studies of the zircon age population in sediments indicate the dominant source is from the Musgrave Province, with minor contribution from the Albany–Fraser Orogen to the west (Reid and Hou 2006). The high zircon content reflects a combination of sorting during transport in fluvial and coastal environments over long distance, with possible recycling through Palaeozoic sandstones of the Officer Basin.

Jacinth and Ambrosia formed on the western, basinward side, of the Ooldea barrier system with HM concentrated on a prograding beach complex that developed in a ‘J-shaped’ bay. A prominent headland at the southern end of the bay is the result of sand accumulation on shallow crystalline basement of Palaeoproterozoic metagranite, part of the Fowler Domain of the western Gawler Craton.

The Jacinth deposit is 900 metres wide and 5 km long.
The Ambrosia deposit is 850 metres wide and 2.2 km long.
[10/31/2018 Corporate Presentation, p. 21]

Mining method: Dry mining, dozer trap to mining unit.
[10/31/2018 Corporate Presentation, p. 18]

Operations at Jacinth-Ambrosia in South Australia moved from the Jacinth deposit to the Ambrosia deposit in August 2019.

Mining scheduled to return to Jacinth at end of Ambrosia mine life.
[05/12/2020 Corporate Presentation, p. 13]

Dry mining and ore concentrating activities occur on site and produce a heavy mineral concentrate through gravity separation. The heavy mineral concentrate is transported to Iluka’s mineral separation facilities in Australia for the production of final products of zircon, rutile and ilmenite.
[06222017_Media_release, p.2]

Wet Concentrator:
- Vibrating screens to remove grit from ore slurry
- Cyclones remove fine material (clay/slimes) from ore slurry
- slimes to thickener
- sand fraction to spirals
- Surge bin de-couples mining unit from concentrator and regulates feed to spirals
- Spirals use gravity to separate heavy minerals from quartz
- Heavy mineral concentrate dewatered and stockpiled
- Some sand stacked (in-pit tails cell construction)
- Remaining sand is pumped to cells with slimes
Production Capacity: Wet concentrator ~1,000tph; Heavy mineral concentrate ~120tph.
[10/31/2018 Corporate Presenta ........